/*
 * Copyright (C) 2010-2018 Gordon Fraser, Andrea Arcuri and EvoSuite
 * contributors
 *
 * This file is part of EvoSuite.
 *
 * EvoSuite is free software: you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as published
 * by the Free Software Foundation, either version 3.0 of the License, or
 * (at your option) any later version.
 *
 * EvoSuite is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * Lesser Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with EvoSuite. If not, see <http://www.gnu.org/licenses/>.
 */

package org.evosuite.contracts;

import org.evosuite.PackageInfo;
import org.evosuite.testcase.execution.CodeUnderTestException;
import org.evosuite.testcase.execution.Scope;
import org.evosuite.testcase.statements.MethodStatement;
import org.evosuite.testcase.statements.Statement;
import org.evosuite.testcase.variable.VariableReference;

import java.util.List;
import java.util.Set;


/**
 * <p>UndeclaredExceptionContract class.</p>
 *
 * @author Gordon Fraser
 */
public class UndeclaredExceptionContract extends Contract {

    /* (non-Javadoc)
     * @see org.evosuite.contracts.Contract#check(org.evosuite.testcase.StatementInterface, org.evosuite.testcase.Scope, java.lang.Throwable)
     */

    /**
     * {@inheritDoc}
     */
    @Override
    public ContractViolation check(Statement statement, Scope scope, Throwable exception) {
        if (!isTargetStatement(statement))
            return null;

        if (exception != null) {
            Set<Class<?>> exceptions = statement.getDeclaredExceptions();

            if (!exceptions.contains(exception.getClass())) {
                if (exception instanceof CodeUnderTestException)
                    return null;

                StackTraceElement element = exception.getStackTrace()[0];

                // If the exception was thrown in the test directly, it is also not interesting
                if (element.getClassName().startsWith(PackageInfo.getEvoSuitePackage() + ".testcase")) {
                    return null;
                }

                /*
                 * even if possible handled by other contracts, that does not mean
                 * they check the signature.
                 * TODO: Not sure I can follow, what does that have to do with the signature
                 */
                // Assertion errors are checked by a different contract
                if (exception instanceof AssertionError)
                    return null;
				/*
				// NullPointerExceptions are checked by a different contract
				if (exception instanceof NullPointerException) {
					return true;
				}
				*/
                if (statement instanceof MethodStatement) {
                    // hashCode and toString are covered already
                    String methodName = ((MethodStatement) statement).getMethod().getName();
                    if (methodName.equals("toString") || methodName.equals("hashCode")) {
                        return null;
                    }

                }


                return new ContractViolation(this, statement, exception);
            }
        }

        return null;
    }

    @Override
    public void addAssertionAndComments(Statement statement,
                                        List<VariableReference> variables, Throwable exception) {
        statement.addComment("Throws undeclared exception: " + exception.getMessage());
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public String toString() {
        return "Undeclared exception check";
    }
}
